You want to wire them all in parallel. Take one lead from each bulb on a post and tie them together. Then tie the other lead from each bulb together. That's per post, you should not have 2 wires, which wneh connected to 6V will light all 3 bulbs on that post. Now repeat for the posts. Tie one lead of each post together. Then tie the other lead from each post together. When you connect this all up to 6V, every light should come on. I'd use some sort of 6V power supply, or even a few volts lower to extend the bulb life. 15 bulbs on batteries won't last very long - the batteries, I mean. 4.5-5 volts would be good, the bulbs wouldn;t be glaringly bright then, and they last a lot longer when the voltage is reduced. Unless they are actually 12 volt bulbs and you're already runnign them ar reduced voltage by using 6V.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for getting back to me so quickly Randy! On a totally different railroad forum, they suggested the same exact thing where I would take one lead from every bulb and so on and so forth.
Again, thanks for the quick reply and the advice!
Steve